%{
 * Copyright (C) 2013-2020, The Regents of The University of Michigan.
 * All rights reserved.
 * This software was developed in the Biped Lab (https://www.biped.solutions/) 
 * under the direction of Jessy Grizzle, grizzle@umich.edu. This software may 
 * be available under alternative licensing terms; contact the address above.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * The views and conclusions contained in the software and documentation are those
 * of the authors and should not be interpreted as representing official policies,
 * either expressed or implied, of the Regents of The University of Michigan.
 * 
 * AUTHOR: Bruce JK Huang (bjhuang[at]umich.edu)
 * WEBSITE: https://www.brucerobot.com/
%}

function [LiDARTag, AprilTag] = get4Corners(opt, mat_file_path, bagfile, target_len, pc_iter, num_scan)
    pc = loadPointCloud(mat_file_path, bagfile);
    X = getPayload(pc, pc_iter, num_scan);
    
    % cost
    opt = optimizeCost(opt, X, target_len);
    target_lidar = [0 -target_len/2 -target_len/2 1;
                    0 -target_len/2  target_len/2 1;
                    0  target_len/2  target_len/2 1;
                    0  target_len/2 -target_len/2 1]';
    LiDARTag.corners = inv(opt.H_opt) * target_lidar;
    LiDARTag.corners = sortrows(LiDARTag.corners', 3, 'descend')';
    LiDARTag.four_corners_line = point3DToLineForDrawing(LiDARTag.corners);
    LiDARTag.points = X;

%             HCamera = getAprilTagPose(app, app.image_num);
    AprilTag.corners = getAprilTagCorners(bagfile);
%             AprilTag.undistorted_corners = getApriltagUndistortedCorners(app, AprilTag.corners);
    AprilTag.four_corners_line = [];
end